This may belong under "rehab," but this also requires some training protocol, so it's going here
The basic upper-body pushing motion is ideally accomplished with little or no shoulder/scapular elevation in order to fully engage the pectoral muscles. Assuming a person has developed over the years a motor recruitment pattern of shrugging in anticipation and execution of a pushing movement, to the point where the trap (over)activate even when consciously depressing the shoulder, how would you suggest this be re-trained? FWIW, the same shrugging activation/action occurs with just about any arm articulation.
My initial thought is to minimize pressing movements above parallel (relative to the ground when standing) while incorporating more rows, pull-ups/downs (maybe even rope climbing if the shoulders can remain depressed), wall slides, reverse shrugs, pull-aparts, and maybe even Turkish get-ups for the shoulder stabilization (as long as the scapula can stay depressed). Basically, this person needs major scapular depression strengthening and motor recruitment rewiring, but that's a lot of stuff to work into the training protocol without being the only thing worked on. Thoughts?